A 19-year-old Jordanian citizen accused of trying to blow up a downtown Dallas skyscraper told a federal magistrate this morning at his first court appearance that he understands the charges against him.

Hosam Maher Husein Smadi, who was provided a court-appointed attorney, is charged with trying to detonate a weapon of mass destruction. He is expected to enter a plea at a later hearing.

Smadi was arrested Thursday after he parked a vehicle laden with government-supplied fake explosives in the underground parking garage of Fountain Place, a 60-story tower at Ross Avenue at Field Street, authorities said.[Hosam Maher Husein Smadi]Hosam Maher Husein Smadi

The arrest was part of an FBI sting operation that began after an agent monitoring an online extremist Web site discovered Smadi espousing jihad against the U.S. more than six months ago.